Problems moving from 2 independent drives to RAID1 configuration

Question

Hi: My NAS200 has been running successfully configured as two independent drives: Public Disk 1/ and Public Disk 2/. I will refer to these as PD1 and PD2. I mostly use PD1 and have been using PD2 to make occasional backups of PD1 (I didn't like the idea of running in mirrored Raid1 mode based on a prior experience). Today I was trying to clone the contents of PD1 and decided to try turning on the RAID1 function, thinking it would make an exact duplicate of PD1 on PD2. My plan was to then break up the RAID mirror again and end up with two identical copies of PD1. However, after the RAID mirroring finished (took about 6 hours), I can no longer see PD1 or PD2 on the mirrored disks, nor Public Disk (PD) for that matter. Can anyone tell me what has happened and how I might recover from it? I have access to a SATA-USB converter and can use it to mount each individual disk onto either a linux or Windows system (via ext2ifs software). When I do this (on Windows), I see that there are three partitions on the disk, and I can name them with ext2ifs, but I can't see any of the contents. I'm currently running DiskInternals Linux Recovery 2.7 on Windows and it is scanning the disk for lost files. It seems to be finding data, but is running very slowly (20 minutes for 3%). Any leads appreciated. Thanks in advance! Maurice Lampell
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Answer 1

The file system is XFS if you have the NAS200 configured for journaled file system, or ext2 if you are using unjournaled file system. ext2ifs can read (and write?) ext2 under Windows but XFS is not supported by any Windows software that I'm aware of.
The RAID configuration is independent from the journaled vs non-journaled configuration: you can have journaled non-raid, journaled raid, non-journaled non-raid and non-journaled raid. RAID configurations are implemented using mdadm.
You can download a SystemRescueCD image from the link in my signature to access the files on the disks from a PC. You burn that image to a CD and boot from it. SystemRescueCD understands SATA disks connected via a USB-SATA dongle, you just need to be able to boot from a CD-ROM drive which is something that all PCs less than about 10 years old can do. SystemRescueCD supports all the necessary file systems and I believe it automatically tries to mount any RAID-formatted disks. The partitions on the hard disk are (1) your data, (2) configuration files and (3) swap. So if you want to recover files, you can ignore the second and third partitions.
I don't think the NAS can convert the configuration from separate disks to RAID without reformatting, so the files that were there in separate-disk mode are propbably lost. You may need another tool to recover the files.
I don't know why your Public Disk shares don't show up, unless you made a change to the configuration so that the shares are hidden from your user name. If you have the web GUI configured to hide the share from guest logins, then maybe you're logged in as guest because you have "change failed logins to guest logins" enabled; you should disable this option.
Your plan of mirroring the disks and then breaking the mirror to put one of the drives away as backup is not a good one, IMHO (and by the way, you really shouldn't remove the drive while the NAS is running). When the NAS loses a drive from the RAID, it will try to rebuild the RAID as soon as you restart with a second drive installed, and it will give the existing drive priority over the older one, so instead of restoring a backup after you lose your files, it will overwrite the backup with the other drive's data so you lose the lost files from the backup too. Also, rebuilding a mirror takes extremely long on the NAS200. It's better to use Separate Disks and run a scheduled backup from one disk to the other; if you delete a file by accident you only have to retrieve that one lost file which takes seconds instead of hours.
===Jac
Frequent NAS200 Answers:
1. DISABLE the "convert failed logins to guest logins" option to fix permission problems.
2. NEVER insert or remove hard disks while the power is on. NAS200 doesn't support hot swapping.
3. ALWAYS use the power button to turn the NAS200 off, don't just unplug it.
4. Don't trust RAID. Make BACKUPS!
5. To ACCESS the disks directly, you will need ext2 and/or XFS file systems. I recommend using SystemRescueCD.
6. Disks will get HOT with standard fan, use "green" disks or consider replacing the fan.
7. FTP server is insecure and doesn't work behind a NAT router. Use my firmware and SCP instead.
8. MY FIRMWARE supports SSH shell prompt and SCP for secure file access, and allows running other software.